It is known in the art to manufacture shoes by using a last. A full slip-on last construction is known wherein an upper, including a sock disposed on the bottom and extending between the bottom left and right sides of the shoe, is assembled in one piece prior to fitting the upper onto the last. The sock is conventionally provided in two pieces, one-half being joined to one side of the upper, and one-half of the sock being joined to the other half of the leather upper. The sock halves are joined to the leather upper usually by gluing, and an overlap of sock and leather materials is necessary for this purpose.
A central stitch is then made to join the free sock half ends down the center of the sole. Thereafter, the upper is fitted onto a last and a sole is glued or otherwise attached to the upper. The last is then removed from the completed shoe.
Certain problems arise when athletic shoes, and in particular leather athletic shoes, are attempted to be made with the conventional full slip-on last method of construction. First, the last and the sock halves must overlap in three different places; one on the left side of the shoe, one on the right side of the shoe, and one down the middle of the shoe. These three overlaps each require an additional strip of material. Second, the central stitch down the middle of the inner sole will be felt by the wearer. Third, the conventional construction depends on the joint between the bottom sock halves to prevent separation of the shoe sides. The sock must therefore be of a relatively strong woven fabric. There is therefore no opportunity to use cushioning material for the sock portion, such as a nonwoven fabric.
Therefore a need exists in the industry to provide a method of athletic shoe construction whereby the number of overlapping material layers is reduced, thereby saving material costs. Furthermore, a need exists to provide a full slip-on lasted athletic shoe that gives enhanced comfort to the wearer.